I have a button similar to below
<button id="uniqueId" onclick="runMethod(this)">Submit</button>
What I'm trying to do is stop the runMethod from running, until after I've done a check of my own. I've tried using the stopImmediatePropagation function, but this doesn't seem to have worked. Here's my jQuery:
$j(document).on('click', '#uniqueId', function(event) {
event.stopImmediatePropagation();
if(condition == true) {
// continue...
} else {
return false;
}
return false;
});
Note: runMethod basically validates the form, then triggers a submit.
What you want to do, especially in the way that you want to do it, requires a some sort of workaround that will always be a bit fiddly. It is a better idea to change the way the button behaves (e.g. handle the whole of the click event on the inside of the jQuery click() function or something along those lines). However I have found sort of a solution for your problem, based on the assumption that your user will first hover over the button. I am sure you can extend that functionality to the keyboard's Tab event, but maybe it will not work perfectly for mobile devices' touch input. So, bear in mind the following solution is a semi-complete workaround for your problem:
$(document).ready(function(){
var methodToRun = "runMethod(this)"; // Store the value of the onclick attribute of your button.
var condition = false; // Suppose it is enabled at first.
$('#uniqueId').attr('onclick',null);
$('#uniqueId').hover(function(){
// Check your stuff here
condition = !condition; // This will change to both true and false as your hover in and out of the button.
console.log(condition); // Log the condition's value.
if(condition == true){
$('#uniqueId').attr('onclick',methodToRun); // Enable the button's event before the click.
}
},
function(){
console.log('inactive'); // When you stop hovering over the button, it will log this.
$('#uniqueId').attr('onclick',null); // Disable the on click event.
});
});
What this does is it uses the hover event to trigger your checking logic and when the user finally clicks on the button, the button is enabled if the logic was correct, otherwise it does not do anything. Try it live on this fiddle.
P.S.: Convert $ to $j as necessary to adapt this.
P.S.2: Use the Javascript console to check how the fiddle works as it will not change anything on the page by itself.
Your problem is the submit event, just make :
$('form').on('submit', function(e) {
e.preventDefault();
});
and it works. Don't bind the button click, only the submit form. By this way, you prevent to submit the form and the button needs to be type button:
<button type="button" .....>Submit</button>
Assuming there's a form that is submitted when button is clicked.
Try adding
event.cancelBubble();
Hence your code becomes:
$j(document).on('click', '#uniqueId', function(event) {
// Don't propogate the event to the document
if (event.stopPropagation) {
event.stopPropagation(); // W3C model
} else {
event.cancelBubble = true; // IE model
}
if(condition == true) {
// continue...
} else {
return false;
}
return false;
});
Your code is mostly correct but you need to remove J:
$(document).on('click', '#uniqueId', function(event) {...
You also need to remove the onClick event from the inline code - there's no need to have it there when you're assigning it via jQuery.
<button id="uniqueId">Submit</button>
Related
I have a jQuery change event for when a user changes a given SELECT element. However the event may also be triggered by a third party script. What I want to do is detect whether the event was triggered programmatically or by the user.
I have tried the accepted solution in this question Check if event is triggered by a human
But note the JSFiddle in this answer is for a click event rather than a change event.
To demonstrate I amended the fiddle and created this one: http://jsfiddle.net/Uf8Wv/231/
If you try this in latest Firefox or Chrome, you will see that the alert human is being shown even when the event was triggered programmatically.
I have tried event.originalEvent.isTrusted but that doesn't work in all browsers. Can anyone help?
I have added mouseenter and mouseleave events. The idea is that it's a human if the click coincided with a mousepointer being over the element. See:
http://jsfiddle.net/Uf8Wv/232/
$("#try").mouseenter(function(event) {
mouseover = true;
});
// ... etc.
I can't think of any other way.
You can find some vague difference between click and emulated click using this code:
$(document).on('change', "#try", function (event) {
//some difference appear in the next line
console.log(event.delegateTarget.activeElement);
//no difference
if (event.originalEvent === undefined) {
alert('not human')
} else {
alert(' human');
}
event.delegateTarget = null;//doesn't help
});
$('#click').click(function (event) {
$("#try").click();
});
Click on the checkbox logs <input id="try" type="checkbox">.
Click on the button logs <button id="click">.
But...
Run $("#try").click(); from console before any clicks logs <body> and after the click result of the last click.
Generally JS can always fake any client event. So isTrusted is never trusted.
You can listen to the click event as well, and modify a variable. The change event seems indeed to be quite similar wheter it's a real click or a script triggered click, but the click on #try event won't be the same. And since click is triggered before change, you have time to set a switch.
Like this for example:
var realClick;
$("#try").change(function(event) {
console.log('change')
if (!realClick) {
alert('not human')
} else {
alert(' human');
}
});
$("#try").click(function(event) {
console.log('click')
// originalEvent is one way, but there will be many differences
if (event.originalEvent) {
realClick = true;
} else {
realClick = false;
}
});
// Since this is called from outside, better not put
// any controls here.
$('#click').click(function(event) {
$("#try").click();
});
http://jsfiddle.net/2xjjmo09/3/
What really worked for me is:
if ((event.originalEvent.isTrusted === true && event.originalEvent.isPrimary === undefined) || event.originalEvent.isPrimary === true) {
//Hey hooman it is you
//Real CLick
}
Tested with jQuery version 3.5
You can easily detect whether the click event on the button is actually triggered by mouse click or not. By doing,
$('#click').click(function(ev) {
if (ev.which !== undefined && ev.button !== undefined) {
$("#try").click();
}
});
Here's the Fiddle
Note: Beware of either ev.which or ev.button could result in 0 on some browser for left-click.
You can check for if event.srcElement (which is source element on which event is triggered) is equal to event.currentTarget something like:
$("#try").change(function(event) {console.log(event,event.target,event.currentTarget,event.srcElement)
if (event.currentTarget=== event.srcElement) {
alert(' human')
} else {
alert(' not human');
}
});
Fiddle: http://jsfiddle.net/Uf8Wv/234/
I've got a 'catch 22' in Chrome. I cannot programmatically select a radio button within a click event if any other function bound to the same event makes a call to preventDefault().
For example, I have a radio button with a parent element bound to a click event in which preventDefault() is called. If the radio button is clicked directly it is not checked. This is to be expected. However, I actually need the radio button to be selected so within code I attempt to check it in another function bound to the click event: $(this).prop('checked', true);.
Oddly, this doesn't work and I cannot remove the call to preventDefault() or disable propagation because it is in third party code that I need to run.
Is this a bug? Any suggested workarounds?
Here is an example:
http://jsfiddle.net/LnLuk4st/
UPDATE:
I have tried #RGraham's suggestion. His example clearly works, but oddly it does not work in the context of my code. #RGraham's code had a syntax error which made it appear to be working.
Here's some context:
// Remember kendo tab
$(".k-tabstrip").each(function () {
var $tabStrip = $(this);
var $tabs = $tabStrip.find(".k-tabstrip-items .k-item");
var tabCookie = "Current_Tab_" + $tabStrip.attr("id");
// On tab change, set cookie
$tabs.click(function () {
createCookie(tabCookie, $(this).attr("aria-controls"), 1);
$tabStrip.parent().css({ 'min-height': $tabStrip.parent().height() });
if ($(this).is('input')) { // Doesn't eval to true, 'this' is always a '.k-item'.
$(this).prop("checked", true);
} else {
// Never works if the input is clicked directly
$(this).find('input').prop("checked", true);
}
});
// #RGraham's suggestion...
$tabs.on('click', 'input', function() {
$(this).prop("checked", true); // Line reached but doesn't work either :(
});
// If cookie set, select tab
var tab = readCookie(tabCookie);
if (tab) {
$tabs.each(function () {
if ($(this).attr("aria-controls") == tab) {
$(this).click();
}
});
}
});
I still believe this behaviour to be a bug but I have found a workaround.
Capture the click of the radio button directly, prevent propagation, then programmatically click the parent of the radio button. This allows the third party code to run without applying preventDefault to the radio button.
// preventDefault bug fix.
$tabs.find("input").click(function (e) {
e.stopPropagation();
$(this).parent().click();
});
I have twp problems
Mark up for the link
DisplaySpreadsheetData
1)
Under document.ready i have this line of code to make sure the link is disabled by default but it does not work.
$('#displaySpreadSheetLink').bind('click', disableLink);
Code to disable the link
var disableLink = function (e) {
e.preventDefault();
return false;
}
2)
when the link is clicked i want to make sure that if checkFile() returns true the link should be disabled
$('#displaySpreadSheetLink').click(function (e) {
if (checkFile()) {
e.preventDefault();
}
});
There are two problems here. How can i correct the first problem and for the second one i think e.preventDefault() does not get executed even if checkFile() returns true.
Can anyone help please?
You might have an issue because you've actually bound two click events to your link. You should unbind the disableLink function before you bind the new functionality:
function disableLink(e) {
e.preventDefault();
// don't use return false here.
}
$(function() {
$('#displaySpreadSheetLink').click(disableLink);
});
// later on
$('#displaySpreadSheetLink').unbind('click').click(function (e) {
if (checkFile()) {
e.preventDefault();
}
});
Also, double-check your logic for checkFile(). Just based on the name I would assume, having never seen your code before, that you'd want to prevent the default behavior if checkFile() fails. Are you sure you don't want if (!checkFile()) { ... }?
Another approach might be to deal with only a single event, but take into account some extra state information as to whether the default behavior should execute or not:
(function($) {
var loaded = false;
$('#displaySpreadSheetLink').click(function(e) {
if (!loaded || checkFile()) {
e.preventDefault();
}
});
$(function() {
loaded = true;
});
})(jQuery);
Instead of disabling a link with a function after the page loads, you should change the HTML to be disabled initially by using a <span> with a CSS class that looks like a disabled link.
Instead of calling checkFile() every time the user clicks the link, have code in the sections that can alter whether checkFile() is true or false. For example, if checkFile() becomes true after a file is uploaded, put code in the file upload function to enable the link by replacing the <span> with an <a>, and link-disabling code in the appropriate places where checkFile() might become false again.
Merely using preventDefault() will make the link look clickable, which is probably bad UI design if it actually does nothing.
I have a button in my form. I need my form to be processed after the first click (or pressing Enter) on the button, and after that, if some conditions would be true, I do something like submitting the form by the second click or pressing Enter key on the button.
What do you think I have to do?
Create a (boolean) variable that saves your state, which is set to true when the first click (or action) has happened and your condition is true. Then submit on the second action when the variable is true.
If the condition has to be matched on both clicks (I guess so) consider the following:
$(function() {
var first = false;
$("form").submit(function() {
if(first && checkCondition())
submit();
if(!first && checkCondition())
first = true;
e.preventDefault();
});
});
so in basic code:
var answered = false;
$(function() {
$("form").submit(function() {
if(answered == false) {
answered = true;
return false;
}
});
});
If I've understood what you're trying to do correctly, you could bind an event handler to the submit event. That event handler will handle your validation, but if you use the jQuery one method, it will only be executed once. The next time the submit event is triggered, the form will submit as usual:
$("yourForm").one("submit", function(e) {
e.preventDefault(); //Stop the form from being submitted
//Do stuff
});
The result is effectively the same as #Manuel van Rijn's answer, but using jQuery's one just makes it a bit shorter and cleaner in my opinion. However, this could also add a slight performance benefit, as the event handler is unbound after it's execution and won't be called again.
I have a list of radio buttons that I can toggle "yes" or "no" to using Javascript.
$(document).ready(function(){
$('#select-all').click(function(){
$('#notifications .notif-radio').each(function(){
$('input[type="radio"]', this).eq(0).attr('checked', true);
$('input[type="radio"]', this).eq(1).attr('checked', false);
});
});
$('#deselect-all').click(function(){
$('#notifications .notif-radio').each(function(){
$('input[type="radio"]', this).eq(0).attr('checked', false);
$('input[type="radio"]', this).eq(1).attr('checked', true);
});
});
});
this works just fine. Now I have a separate piece of code that detects when a user has changed something, and asks them if they want to leave the page.
var stay_on_page;
window.onbeforeunload = confirm_exit;
$('.container form input[TYPE="SUBMIT"]').click(function(){
stay_on_page = false;
});
$('#wrapper #content .container.edit-user form').change(function(){
stay_on_page = true;
});
function confirm_exit()
{
if(stay_on_page){ return "Are you sure you want to navigate away without saving changes?"; }
}
The problem is that if the user uses the first piece of functionality to toggle all radio buttons one way or another. The JS detecting form changes doesn't see that the form was changed. I have tried using .live, but to no avail. Anyone have any ideas?
I do something similar to this by adding change() (or whatever's appropriate, click() in your case I suppose) event handlers which set either a visible or hidden field value, then check that value as part of your onbeforeunload function.
So, my on before unload looks like:
window.onbeforeunload = function () {
if ($('#dirtymark').length) {
return "You have unsaved changes.";
}
};
And, or course, dirtymark is added to the page (a red asterisk near the Save button), when the page becomes dirty.